Milk Allergy vs. Lactose Intolerance

Learn about the differences between milk allergy and lactose intolerance.

Milk allergy should not be confused with lactose intolerance.

A food allergy happens when your immune system overreacts to a specific food protein. When you eat or drink the food protein, it can trigger an allergic reaction. Symptoms can range from mild (rashes, hives, itching, swelling, etc.) to severe (trouble breathing, wheezing, loss of consciousness, etc.). A food allergy can be potentially life-threatening.

Unlike food allergies, food intolerances do not involve the immune system. People who are lactose intolerant are missing the enzyme lactase. Lactase breaks down lactose, a sugar found in milk and dairy products. As a result, people with lactose intolerance are unable to digest these foods. They may experience symptoms such as nausea, cramps, gas, bloating and diarrhea. While lactose intolerance can cause great discomfort, it is not life-threatening.